Allow configuration of a default rendezvous server for use with Sign in with QR

src/IConfigOptions.ts

@@ -207,6 +207,13 @@ export interface IConfigOptions {
             client_id: string;
         }
     >;
+
+    login_with_qr?: {
+        /**
+         * Default rendezvous server to use even if the Homeserver doesn't provide one.
+         */
+        default_rz_server?: string;
+    };
 }
 
 export interface ISsoRedirectOptions {

src/components/views/auth/LoginWithQR.tsx

@@ -24,6 +24,7 @@ import { MatrixClient } from "matrix-js-sdk/src/matrix";
 import { _t } from "../../../languageHandler";
 import { wrapRequestWithDialog } from "../../../utils/UserInteractiveAuth";
 import LoginWithQRFlow from "./LoginWithQRFlow";
+import SdkConfig from "../../../SdkConfig";
 
 /**
  * The intention of this enum is to have a mode that scans a QR code instead of generating one.
@@ -153,9 +154,12 @@ export default class LoginWithQR extends React.Component<IProps, IState> {
     private generateCode = async (): Promise<void> => {
         let rendezvous: MSC3906Rendezvous;
         try {
+            const fallbackRzServer = SdkConfig.get().login_with_qr?.default_rz_server;
+
             const transport = new MSC3886SimpleHttpRendezvousTransport<MSC3903ECDHPayload>({
                 onFailure: this.onFailure,
                 client: this.props.client,
+                fallbackRzServer,
             });
 
             const channel = new MSC3903ECDHv2RendezvousChannel<MSC3906RendezvousPayload>(

src/components/views/settings/devices/LoginWithQRSection.tsx

@@ -25,6 +25,7 @@ import {
 import { _t } from "../../../../languageHandler";
 import AccessibleButton from "../../elements/AccessibleButton";
 import SettingsSubsection from "../shared/SettingsSubsection";
+import SdkConfig from "../../../../SdkConfig";
 
 interface IProps {
     onShowQr: () => void;
@@ -43,7 +44,9 @@ export default class LoginWithQRSection extends React.Component<IProps> {
         const capability = UNSTABLE_MSC3882_CAPABILITY.findIn<IMSC3882GetLoginTokenCapability>(this.props.capabilities);
         const msc3882Supported =
             !!this.props.versions?.unstable_features?.["org.matrix.msc3882"] || !!capability?.enabled;
-        const msc3886Supported = !!this.props.versions?.unstable_features?.["org.matrix.msc3886"];
+        const msc3886Supported =
+            !!this.props.versions?.unstable_features?.["org.matrix.msc3886"] ||
+            !!SdkConfig.get().login_with_qr?.default_rz_server;
         const offerShowQr = msc3882Supported && msc3886Supported;
 
         // don't show anything if no method is available

test/components/views/settings/devices/LoginWithQRSection-test.tsx

@@ -21,6 +21,7 @@ import React from "react";
 
 import LoginWithQRSection from "../../../../../src/components/views/settings/devices/LoginWithQRSection";
 import { MatrixClientPeg } from "../../../../../src/MatrixClientPeg";
+import SdkConfig from "../../../../../src/SdkConfig";
 
 function makeClient() {
     return mocked({
@@ -114,5 +115,18 @@ describe("<LoginWithQRSection />", () => {
             );
             expect(container).toMatchSnapshot();
         });
+
+        it("MSC3882 r1 + default_rz_server", async () => {
+            jest.spyOn(SdkConfig, "get").mockReturnValue({ login_with_qr: { default_rz_server: "https://rz.local" } });
+            const { container } = render(
+                getComponent({
+                    versions: makeVersions({}),
+                    capabilities: {
+                        [UNSTABLE_MSC3882_CAPABILITY.name]: { enabled: true },
+                    },
+                }),
+            );
+            expect(container).toMatchSnapshot();
+        });
     });
 });

test/components/views/settings/devices/__snapshots__/LoginWithQRSection-test.tsx.snap

@@ -83,3 +83,41 @@ exports[`<LoginWithQRSection /> should render panel MSC3882 r1 + MSC3886 1`] = `
   </div>
 </div>
 `;
+
+exports[`<LoginWithQRSection /> should render panel MSC3882 r1 + default_rz_server 1`] = `
+<div>
+  <div
+    class="mx_SettingsSubsection"
+  >
+    <div
+      class="mx_SettingsSubsectionHeading"
+    >
+      <h3
+        class="mx_Heading_h4 mx_SettingsSubsectionHeading_heading"
+      >
+        Sign in with QR code
+      </h3>
+    </div>
+    <div
+      class="mx_SettingsSubsection_content"
+    >
+      <div
+        class="mx_LoginWithQRSection"
+      >
+        <p
+          class="mx_SettingsTab_subsectionText"
+        >
+          You can use this device to sign in a new device with a QR code. You will need to scan the QR code shown on this device with your device that's signed out.
+        </p>
+        <div
+          class="mx_AccessibleButton mx_AccessibleButton_hasKind mx_AccessibleButton_kind_primary"
+          role="button"
+          tabindex="0"
+        >
+          Show QR code
+        </div>
+      </div>
+    </div>
+  </div>
+</div>
+`;